Block-protected braking system

ABSTRACT

The invention relates to a block-protected braking system for a vehicle, comprising an electronic controller ( 22, 24 ) arranged in a housing ( 12 ), a valve block ( 14 ) to accommodate solenoid valves for controlling the hydraulic fluid in the braking system, and a pump motor ( 16 ) for a pump which delivers hydraulic fluid, with the solenoids ( 20 ) of the valves being accommodated in an intermediate body ( 18 ) which is arranged between the valve block ( 14 ) and the housing ( 12 ) of the electronic controller, said intermediate body ( 18 ) comprising electric connecting means ( 34, 38 ) for connecting the electronic controller with the solenoids ( 20 ), and said valve block ( 14 ) and said housing ( 12 ) of the electronic controller being connected with each other by means of the intermediate body ( 18 ).

This application is a continuation of PCT Application PCT/EP95/00493filed Feb. 10, 1995.

The invention relates to a block-protected braking system for vehicleswith the characteristics of the preamble clause of claim 1, as it isknown from DE 40 01 017 A1. This known arrangement, however, does notshow the connection between the valve block and a pump motor for a pumpwhich delivers a hydraulic fluid.

The term “block-protected braking system” herein refers to a unit whichprevents the blockage of braked wheels of a vehicle and, if required,also the spinning of driven wheels (so-called antislip control—ASC).Such a unit comprises at least the following assemblies: an electroniccontroller which generally includes a computer which derivesinstructions for the control of the braking system depending on measureddata (such as e.g. deceleration and acceleration values of the wheels),a valve block which in particular accommodates solenoid valves forcontrolling the hydraulic fluid in the braking system, with the valvesbeing opened or closed, respectively, in accordance with theinstructions generated by the computer, and a pump motor which drives apump which delivers the hydraulic fluid to the master cylinder and/orthe wheel brakes of the vehicle, if the valves are set accordingly.

The system assemblies valve block, pump, and pump motor are oftendesignated as the “hydraulic power unit”.

The present invention relates to the arrangement, assembly andconnection of the cooperating assemblies electronic controller, valveblock, pump motor and pump.

From the state of the art a variety of arrangements of the mentionedassemblies of a block-protected braking system is known. Particularreference shall be made to EP-A-0 105 219, DE-A-38 13 138 and DE-A-38 13139.

With respect to the geometrical arrangement of the above-mentionedcomponents and their electrical and mechanical connections, it is ofessential importance to achieve an assembly as compact (minimum spacerequirement) as possible. Moreover, lines for the electrical connections(in particular cable trees) are to be reduced with respect tocircumference and length, and the assembly of the parts must be assimple as possible. In addition, the entire arrangement should belimited to as few components as possible. Moreover, the connection ofthe individual components shall be electrically and mechanically safeand have a low susceptibility to failures. The subject matter of thepresent invention implies an improvement with respect to all thesetechnical problems.

In view of the above-mentioned set of technical objects, the electricaland mechanical assembly of the pump motor according to the state of theart need to be improved. It is also to be noted that under the aspect ofthe above-mentioned mechanical and, especially, electrical safety ofassembly and connection of the components, a sealing of the housingwhich encompasses the components becomes necessary, especially a sealingagainst humidity, dirt, etc.

EP-A-0 438 553 discloses a valve block where the solenoids of the valvesare combined on a common contact carrier which also contains commonconnectors for connecting the solenoids with the electronic controllerof the braking system. However, an integration of the electrical andmechanical assembly of the pump motor is not provided.

From WO 93/08050 A1 an electrohydraulic unit for the pressure regulationin vehicle braking systems is known, where the valve block is connectdwith a pump motor for a pump delivering hydraulic fluid. In thisarrangement the pump motor, however, is not provided with a shoulderwhich fits into a recess in the intermediate body.

In view of the technical problems as mentioned the invention improves ablock-protected braking system of the above-mentioned type by thecharacteristics of claim 1.

In that the pump motor (or a housing which accommodates the pump motor)comprises a shoulder which is inserted in an accurately fitting andpositive manner into a recess in the intermediate body, and whichcontains an electrical connection line for connecting the pump motorwith the electronic controller, a mechanical and electrical connectionof the pump motor with the electronic controller and also with the valveblock is obtained simultaneously. The intermediate body serves both asan electrical and a mechanical connecting member for all threeassemblies, i.e. the electronic controller, the valve block and the pumpmotor.

Preferred embodiments of the block-protected braking system aredescribed in the dependent claims.

A particularly consequent application of the inventive design isobtained if the pump motor and the housing of the electronic controllerarea also connected to one anothr by means of the intermediate body.

Thus, the invention provides for the connection of the electroniccontroller and the hydraulic power unit (see above) via an intermediatebody which carries all the solenoids of the valves of the hydraulicpower unit. A direct electrical connection from a printed circuit boardof the electronic controller via plug and socket contacts is made toconnection lines which lead to the solenoids. These connection lines areaccommodated in the intermediate body and electrically insulatedtherein.

The inventive arrangement of the components is advantageous in that onlytwo seals are required as a protection particularly of the electroniccontroller against environmental influences (humidity, dirt, etc.), oneof which is disposed between the housing of the electronic controllerand the other is disposed between the intermediate body and the pumpmotor. According to a preferred embodiment the latter is a seal betweenthe intermediate body and a shoulder at the pump motor.

The intermediate body which serves to connect the componentselectrically and mechanically can be manufactured as an economicalinjection-molded plastic part, with the solenoids together with theelectrical conductors being embedded. The electrical conductors can alsobe manufactured in a simple manner as a punched grid.

It is also advantageous that the braking system according to theinvention allows the arrangement of the electronic controller beneaththe hydraulic power unit. This enables a particularly compactarrangement of the parts.

According to another preferred embodiment of the invention, the pumpmotor comprises a shoulder which is independent (spatially separated) ofthe intermediate body and which accommodates an electrical connectionbetween the electronic controller and the pump motor. This separationbetween the housing and the valve block on the one hand, and the housingand the pump motor on the other hand, enables a shorter line routing andprovides for a better decoupling of the respective signals. Moreover,the intermediate body can be of a simpler design because it is notadapted to encompass the shoulder.

In order to obtain a particularly stable connection between the housingand the valve block and between the the housing and the pump motor whichis also reliably sealed against dust, humidity, oil, etc. the housingcomprises a first support for the intermediate body and a second supportfor the shoulder. In a particularly preferred embodiment, the first andthe second support are connected with the housing in a dustproof and/orhermetically sealed manner.

In addition, the first and/or the second support can be connected with aprinted circuit board in the housing in a dustproof and/or hermeticallysealed manner. This allows a further increase of the reliability.

The electric connection between the pump motor and the housing of theelectronic controller can also be be made by means of plug and socketcontacts, with the second support accommodating plug and socket contactsbetween the electronic controller and the pump motor.

Each of the first and/or second support is preferably provided with aseal which ensures a dustproof and/or hermetically sealed connectionbetween the valve block or the pump motor and the housing, respectively.

According to a preferred embodiment the intermediate body and/or theshoulder are arranged laterally adjacent to or in a recess in asupporting plate of the valve block or the pump motor, respectively, andprovide for the connection between the first or the second support,respectively. In addition, the housing of the electronic controller canbe secured at the supporting plate e.g. by means of a suitable screwconnection. This is advantageous in that the overall arrangement has aconsiderably flatter design than the first embodiment because thetransverse dimension of the intermediate body is omitted here. Moreover,the cooling function is improved because the housing of the electroniccontroller is directly contacting the heat conductive (metallic)supporting plate which in turn contacts the heat conductive valve blockwhich is also heat conductive due to the omission of the intermediatebody.

In a preferred embodiment the first and/or second support each areencompassed by a seal which bears upon the respective support in anaxial and a radial direction, and the intermediate body or the shoulder,respectively, encompasses the respective seal.

The supporting plate can additionally be screwed to the valve blockand/or to the pump motor. In particular, this can also be done by meansof screw-type formed dampening chamber plugs which are already present alarger volume of the dampening chamber can be provided by acorresponding shape of the dampening chamber plug.

In the following, an embodiment of the invention will be described inmore detail with reference to the drawing, in which:

FIG. 1 is a schematic, partially sectional, side view of the assembliesof interest of a block-protected braking system.

FIG. 2 is a plan view of an intermediate body which is used in anarrangement according to FIG. 1, with FIG. 1 showing a sectional viewthrough the intermediate body along line I-II in FIG. 2.

FIG. 3 is a schematic side view of second embodiment with a partialelevational view of part of a housing, a pump motor and a valve block.

FIG. 4 is a schematic side view of the embodiment of FIG. 3 in anenlarged representation compared to FIG. 3 with a partial elevationalview of part of the housing, the pump motor and the valve block.

FIG. 5 is a schematic bottom view of the embodiment of FIG. 3 with thehousing removed from the pump motor or valve block, respectively.

FIG. 6 is a schematic sectional side view through a dampening chamberwith a screwed-in dampening chamber plug in a larger scale than that ofFIG. 3.

FIG. 1 shows a unit 10 with the following assemblies of ablock-protected braking system:

An electronic controller of the braking system accommodated in a housing12, with the electronic controller indicated here by a printed circuitboard 22 and symbolically by a circuit element 24 only; a valve block 14which accommodates the solenoid valves required for a block-protectedbraking system (if required, with ASC) and associated line parts (whichare connected with the individual wheel brakes of the vehicle—notshown); and a pump motor 16 which drives a pump which delivers hydraulicfluid in a manner known per se to the master cylinder and/or the wheelbrakes (not shown). In the illustrated first embodiment the pump(usually a piston pump) is arranged in the valve block 14.

For the electrical and mechanical connection and the assembly of thementioned assemblies 12, 14 and 16, an intermediate body 18 made fromplastic material is used. The intermediate body 18 is arrangedvertically above the housing 12 of the electronic controller andaccommodates all solenoids 20 for the individual solenoid valves of thevalve block 14.

FIG. 2 is a plan view of the intermediate body 18. As can be seen, foursolenoids 20 are accommodatd in the intermediate body 18, with each ofthe solenoids 20 surrounding a hollow space 32 in which the valve (notshown) or at least a component of the valve (the armature) is arranged.

FIG. 1 shows two exemplary contact pins 26, 28 which project upwardsfrom the printed circuit board 22. In a direction vertically to thedrawing plane several of such electric contact pins 38 are arranged oneafter the other, as can be seen from FIG. 2.

On the housing 12 a supporting plate 30 is attached with a large area ofthe intermediate body 18 being in contact with same.

An electric line 34 leads to each of the four solenoids 20, whichconnects each solenoid with a contact terminal 38. The line 34 and thecontact terminals 38 are accommodated in the intermediate body 18, witheach contact terminal 38 being arranged in one hollow space each in theintermediate body 18. The intermediate body 18 which extends in ahorizontal direction comprises a shoulder 18 a which extends verticallydownwards into the housing 12 of the electronic controller andaccommodates the contact terminals 38. The shoulder 18 a of theintermediate body 18 is provided with openings in its bottom facethrough which the contact pins 28 can be pushed for an electricallyconducting engagement with the contact terminals 38.

The pump motor 16 comprises a motor block 40 from which a shoulder 40 aprojects vertically downwards. The shoulder 40 a of the motor blockaccurately fits a recess 36 which is formed in the intermediate body 18(see also FIG. 2). The shoulder 40 a of the motor block 40 accommodatesa contact terminal which similar to the above-described contactterminals of the solenoids receives a contact pin 26 of the electroniccontroller in order to provide an electrical connection between theelectronic controller and the pump motor 16. The shoulder 40 a alsoeffects a mechanical mounting of the pump motor 16 to the remainingassemblies via the recess 36 in the intermediate body 18. The innerspaces of the pump motor and the housing 12 of the electronic controllerare sealed against environmental influences by means of an O-ring 46.Only one further single seal 44 is required to achieve the sealing ofthe housing 12 and the parts of the intermediate body, which might besusceptible to failure, against environmental influences.

The pump motor 16 is secured at the valve block 14 by means of two screwbolts 50, 52.

A nose 48 of the valve block 14 encompasses the supporting plate 30 towhich the housing 12 of the electronic controller is attached. Anadditional screw connection by means of a correspondingly formeddampening chamber plug 88 ensures a reliable mechanical mounting of thehousing 12 at the valve block 14.

FIGS. 3 to 6 illustrate another embodiment of the invention. Parts andassemblies which are similar to those in FIGS. 1 and 2 are assignedidentical reference numerals and their repeated detailed descriptionwill be omitted.

In this embodiment the pump motor 16 comprises a shoulder 60 which isindependent of the intermediate body 18 and which accommodates anelectric connection in the form of plug and socket contacts 26, 42between an electronic controller 22, 24 and the pump motor 16. Theshoulder 60 is spatially separated from the intermediate body andprojects immediately away from the pump motor 14. In this embodiment theintermediate body 18 is arranged in a similar manner so as to projectfrom the valve block 14. The intermediate body 18 thus accommodatesparts of the solenoids 20 of the valves 61 and extends laterally beyondthe supporting plate 30 to a first support 62 for the intermediate body18 which is arranged at the housing 12. On the other side, the shoulder60 extends in a similar way laterally beyond the supporting plate 30 toa second support 64 for the intermediate body 18 which is arranged atthe housing 12.

The first and the second support 62 and 64 are connected with thehousing 12 by means of bonding, potting or the like in a dustproof andhermetically sealed manner. Moreover, the first and the second support62, 64 are connected with the printed circuit board 22 in the housing 12in a dustproof and hermetically sealed manner.

The first and the second support 62 and 64 are provided with a laterallyprojecting circumferential collar 62 a, 64 a each against which a shapedseal 80, 82 each bears which surround the free edge of the first and thesecond support 62 and 64. Thereby a dustproof and hermetically sealedconnection between the valve block 14 or or the pump motor 16,respectively, and the housing 12 is achieved.

Alternatively, the intermediate body 18 and the shoulder 60 can also bearranged in a recess of the supporting plate 30 of the valve block 14 orthe pump motor 16, respectively, and provide for the connection with thefirst or the second support 62 or 64, respectively.

The supporting plate 30 is attached to the valve block 14 (see FIGS. 3to 6). For this purpose the supporting plate 30 is screwed against thevalve block 14 by means of the screw-type damening chamber plug 88. Inaddition, a screw 90 can be provided for holding the supporting plate30. An attachment of the supporting plate 30 to the pump motor 16 couldalso be considered. A through hole 94 serves to enable the screwconnection of the housing 12 of the electronic controller with thesupporting plate 30. FIG. 6 shows the cross-section through an expansionchamber 96 and a dampening chamber 98 with the dampening chamber plug 88installed therein.

The embodiment according to the invention improves the heat dissipationbehaviour, the ease of assembly and replacement of the electroniccontroller and the susceptibility to failures and decreases the requiredinstallation space.

What is claimed is:
 1. A block-protected braking system for a vehicle,comprising: an electronic controller (22, 24) arranged in a housing(12); a valve block (14) to accommodate solenoid valves for controllingthe hydraulic fluid in the braking system; a pump motor (16) for a pumpwhich delivers hydraulic fluid and which comprises a shoulder (40 a);and an intermediate body (18) which is arranged between he valve block(14) and the housing (12) of the electronic controller and whichcomprises the solenoids (20) of the valves, an electric connecting means(34), a recess (36) for accommodating the shoulder and electric contacts(38), said intermediate body electrically and mechanically associatingthe valve block (14), he pump motor (16) and the electronic controller(22, 24) with its housing (12) to each other.
 2. A braking systemaccording to claim 1 characterized in that the electric connecting meanscomprise plug and socket contacts (26, 28).
 3. A braking systemaccording to claim 1 characterized in that the intermediate body (18)consists of plastic material into which the solenoids (20) and theelectrical connecting means (34) are potted or embedded by injectionmolding.
 4. A braking system according to claim 1 characterized in thatthe valve block (14) and the pump motor (16) are arranged verticallyabove the housing (12) of the electronic controller (22, 24).
 5. Abraking system according to claim 1 characterized in that the shoulder(60) of the pump motor (16) is independent of the intermediate body (18)and accommodates an electric connection (26, 42) between the electroniccontroller (22, 24) and the pump motor (16).
 6. A braking systemaccording to claim 5 characterized in that the housing (12) comprises afirst support (62) for the intermediate body (18) and a second support(64) for the shoulder (60).
 7. A braking system according to claim 6characterized in that at least one of the first support (62) and thesecond support (64) are connected with the housing (12) in a dustproof,hermetically sealed manner.
 8. A braking system according to claim 6further comprising a printed circuit board (22) disposed within thehousing (12) and characterized in that at least one of the first and thesecond supports (62, 64) are connected with the printed circuit board(22) in the housing (12) in a dustproof hermetically sealed manner.
 9. Abraking system according to claim 6 characterized in that the secondsupport (64) accommodates plug and socket contacts (26) between theelectronic controller (22, 24) and the pump motor (16).
 10. A brakingsystem according to claim 6 characterized in that at least one of thefirst and the second supports (62, 64) are provided with a seal (80, 82)each which effects a dustproof hermetically sealed connection betweenthe valve block (14) of the pump motor (16) and the housing (12),respectively.
 11. A braking system according to claim 10 wherein atleast one of the valve block (14) and the pump motor (16) includes asupporting plate (30) having a recess and characterized in that at leastone of the intermediate body (18) and the shoulder (60) are arrangedlaterally adjacent to or in the recess of a supporting plate (30) of thevalve block (14) or the pump motor (16), respectively, and provides forthe connection with one of the first and the second supports (62, 64).12. A braking system according to claim 11 characterized in that thesupporting plate (30) is screwed to the valve block (14) by means of adampening chamber plug (88).
 13. A braking system according to claim 6characterized in that at least one of the first and the second supports(62, 64) is surrounded by a seal (80, 82) which axially and radiallybears upon the respective support (62, 64), and wherein the intermediatebody (18) or the shoulder (60), respectively, encompass the respectiveseal (80, 82).
 14. A braking system according to claim 12 characterizedin that the housing (12) of the electronic controller is attached to thesupporting plate (30).
 15. A braking system according to claim 1characterized in that the housing (12) of the electronic controller (22,24) is mechanically secured by means of a nose (48) formed at the valveblock (14).